This invention relates generally to apparatus for reducing the consumption of power by controlling the application and removal of power to loads in response to the movement and absence of movement of an object within a prescribed area.
The conservation of energy in general is of paramount concern to all and the conservation of electrical energy and its attendant conservation of fossil fuel used to produce the electrical energy is becoming more critical and of increasing importance.
Various movement responsive control means are known to the prior art, however, as is known to those skilled in such prior art, such prior art apparatus and systems typically suffer from one or more unwanted or undesirable characteristics. For example, the movement responsive light control means disclosed in U.S. Pat. No. 3,459,961 to Ravas, suffers from the undesirable characteristic of the control or sensing means disclosed therein being able to only control the application and removal of power to loads which must be connected to a power source or power sources of the same phase. Obviously, it is highly desirable for simplicity and economy in the arrangement of controlled loads and in the simplicity of the circuit connection for interconnecting the controlled loads with various sources of power to be able to control and connect such loads to power sources of the same or different phase. Further, economy can be achieved by utilizing a single control circuit or apparatus to control a plurality of loads and to be able to connect such loads to different power sources of the same or different phase with only a single control circuit or apparatus.
The other problem generally inherent to prior art movement responsive control apparatus, particularly movement responsive control apparatus for controlling the application and removal of electrical power to room lights such as tungsten filament lamps is the problem known to those skilled in the art as in-rush current which is caused by the switching current or switching voltage produced in switching the electrical power on and off of the tungsten filament lamps. An attendant problem to the inrush current problems, as is further known to those skilled in the art, is that of electro-magnetic interference caused by the switching current.